 
 (defn- circle-of-fifths [major-or-minor]
   (zipmap (case major-or-minor
-            :major [:c-flat :g-flat :d-flat :a-flat :e-flat :b-flat :f 
+            :major [:c-flat :g-flat :d-flat :a-flat :e-flat :b-flat :f
                     :c :g :d :a :e :b :f-sharp :c-sharp]
             :minor [:a-flat :e-flat :b-flat :f :c :g :d
-                    :a :e :b :f-sharp :c-sharp :g-sharp :d-sharp :a-sharp]) 
+                    :a :e :b :f-sharp :c-sharp :g-sharp :d-sharp :a-sharp])
           (range -7 8)))
 
 (defn key-signature [pitch major-or-minor]

(defmethod notes :blues [{:keys [pitch]}]
  (let [minor-pentatonic (pentatonic-scale pitch :minor)
        extra-note       (augment (nth minor-pentatonic 2))]
    (set (concat (take 3 minor-pentatonic) 
                 [extra-note]
                 (drop 3 minor-pentatonic)))))

        letter->number (zipmap "abcdefg" (range 8))
        number->letter (zipmap (range 8) "ABCDEFG")
        base-number    (->> pitch name first letter->number)
        base-notes     (take 7 (map number->letter
                                    (iterate #(rem (inc %) 7) base-number)))
        {:keys [sharps flats]} (key-signature pitch major-or-minor)]
    (map (fn [letter]
           (str letter (when (and sharps (sharps letter)) \#)
                       (when (and flats (flats letter)) \b)))
         base-notes)))

